Spinal myoclonus following neuraxial anesthesia: a literature review

Transient involuntary movement disorder after spinal anesthesia: A case report

BACKGROUND

Spinal anesthesia is commonly used for various surgeries. While many complications occur after induction of spinal anesthesia, involuntary movement is an extremely rare complication.

CASE SUMMARY

Herein, we report the case of a 54-year-old healthy male patient who experienced involuntary movements after intrathecal injection of local anesthetics. This patient had undergone metal implant removal surgery in both the lower extremities; 7 h after intrathecal hyperbaric bupivacaine administration, involuntary raising of the left leg began to occur every 2 min. When the movement disorder appeared, the patient was conscious and cooperative. No other specific symptoms were noted in the physical examination conducted immediately after the involuntary leg raising started; moreover, the patient's motor and sensory assessments were normal. The symptom gradually subsided. Twelve hours after the symptom first occurred, its frequency decreased to approximately once every three hours. Two days postoperatively, the symptoms had completely disappeared without intervention.

CONCLUSION

Anesthesiologists should be aware that movement disorders can occur after spinal anesthesia and be able to identify the cause, such as electrolyte imbalance or epilepsy, since immediate action may be required for treatment. Furthermore, it is crucial to know that involuntary movement that develop following spinal anesthesia is mostly self-limiting and may not require additional costly examinations.

Spinal myoclonus following spinal anaesthesia in a patient with restless legs syndrome

Myoclonus is defined as involuntary muscle contractions that are self-limiting. The presentation can be diverse, and severe movements may cause significant alarm to both patient and practitioner, with the potential for inappropriate management. Although rare, myoclonus has been associated with intrathecal anaesthetics; however, the exact aetiology remains unclear. In this report, we present a case of delayed spinal myoclonus following the administration of intrathecal bupivacaine to a patient with a known history of restless legs syndrome. The aim of this report is to increase awareness of this rare complication and to contribute to the current body of literature in order that the pathophysiology and potential risk factors may be better understood.

Segmental Spinal Myoclonus After a Cervical Transforaminal Epidural Steroid Injection

In clinical practice, cervical transforaminal epidural steroid injection is commonly used for alleviating pain. We report a case of segmental spinal myoclonus that developed after cervical transforaminal local anesthetic and steroid injection. A 39-yr-old man presented involuntary movements of the bilateral upper trapezius muscles after cervical transforaminal epidural steroid injection on the right C6 and C7 roots with a 5 mg of dexamethasone injectate mixed with 0.5 ml of 1% lidocaine and 0.5 ml of normal saline at each level. His myoclonus was semirhythmic and continuously persisted at a frequency of approximately 30 episodes per minute. The myoclonus continued even at rest and during sleep. In addition, it was resistive to stimulus, such as touch and voluntary action. Based on the clinical features, the patient was diagnosed as having a segmental spinal myoclonus. Clonazepam 0.25 mg was administered three times daily. The myoclonus gradually improved and resolved completely within 2 wks. Segmental spinal myoclonus is one of rare complications after cervical transforaminal epidural steroid injection. Clinicians should be aware of the likelihood of this potential complication.